Electroactive site enriched battery-type worm-like cobalt tungstate nanoarchitecture electrode material for performance-enhanced hybrid supercapacitor

Abstract

The supercapacitor performances of stable and highly efficient electrode materials crucially depend on their physicochemical parameters, which are influenced by the preparation conditions and techniques. Herein, the worm-like CoWO4 (CWO) nanoarchitecture is achieved through a facile hydrothermal method followed by pyrolysis. The effect of pyrolysis temperature on the physicochemical properties, such as crystallinity, surface area, porosity, particle size, and morphology of the prepared CWO nanomaterials, is examined. From these observations, the pyrolyzing temperature significantly impacts the physicochemical characteristics and the associated electrochemical performances. Further, the final product's crystallite size increases, and surface area concomitantly fall from 16 to 34 nm and 26.1–12.9 m2 g−1, respectively, as the pyrolyzing process is increased from 400 to 600 °C. The distinct morphological feature of worm-like CWO-A nanostructure pyrolyzed at 400 °C is advantageous to have effective charge transfer and large energy storage capacity. Markedly, the worm-like CWO-A electrode depicts a superior specific capacity of 445 and 284 C g−1 at 1 and 20 A g−1, respectively, suggesting an excellent rate performance. Moreover, the constructed hybrid supercapacitor (CWO-A//AC) attains a maximum energy density of 41.38 Wh kg−1 at a power density of 627.42 W kg−1 with an outstanding long-term cyclic retention and ∼9.3% of capacity loss for 10,000 cycles. Thus, this study highlights that the distinct worm-like CWO-A nanostructure could be a suitable electrode material for supercapacitor applications.